qfd.ppt

Quality Function Deployment

QFD for Software Requirements Management

Guy DavisCarmen Zannier

Adam Geras

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Objectives

Upon completion of this chapter, students will: Understand what Quality Function Deployment (QFD) is Understand how QFD compares to other software

development life cycles Be able to identify the primary QFD tools and concepts Be able to identify the QFD practices that might be

useful in non-QFD working environments

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1. Introduction to QFD

QFDRequirements Engineer

?

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1(a) QFD - Definition

+

VOICE OF THECUSTOMER

QFD

= CUSTOMERSATISFACTION

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1(a) QFD – Definition (Cont.)

[ASI, 2000]

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1(b) QFD - Benefits

[ASI, 2000]

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1(c) QFD - History

QFD

STATISTICALPROCESS CONTROL

DESIGN QUALITY

VALUEENGINEERING

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1(d) Software Engineering Context

Customer

TQM

Software Engineer

SDLC

SQFDRequirements Engineer

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1(e) Requirements Engineering Context

Voice of theCustomerSQFD

Requirements Engineer

Customer

RequirementsPrioritization

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2. QFD Life Cycle Considerations

QFD Process SQFD Process

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2(a) Traditional QFD Phases

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2(b) Adapting QFD to Software

ProductPlanning

MeasurableObjectives

Cu

sto

mer

Vo

ice

Phase 1:Conceive

DesignPlanning

High Leve lDesign

Mea

sura

ble

Ob

ject

ives

Phase 2:Develop

ProcessPlanning

Methods,tools

Hig

h L

evel

Des

ign

Phase 3:Manufacture

ProductionPlanning

Procedures

Met

ho

ds,

to

ols

Phase 4:Deliver

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2(b) SQFD Process

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3. The House of Quality

6. Targets6. Targets

4. Inter-relationships

4. Inter-relationships

2. P

lann

ing

Mat

rix

1. C

usto

mer

Req

uire

men

ts3. Technical

Requirements

3. TechnicalRequirements

5. Roof5. Roof

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3(a) Customer Requirements

StructuredRequirements

Document

Group 1 Group 2 Group 3

Title Card

Group 1 Group 2 Group 3

Title Card

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3(b) Affinity and Tree Diagrams

AttractiveAttractiveUsabilityUsability PerformancePerformance

Facilitates Climbing

Does notrestrict movement

Safe

AccessibleGear Loops

Lightweight

Attractive

Comfortable

Fits overDifferent clothes


Safe


Lightweight

Attractive

Comfortable



Safe


Lightweight

AttractiveComfortable

Fits overDifferent clothes Does not

restrict movement

Safe


Lightweight

AttractiveComfortable


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Exercise 1 – Affinity Workshop

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3(c) The Planning Matrix

Quantifies Customer Requirements. Quantifies Perceptions of Existing Products. Allows adjustment based on design team.

COMFORTABLE 5 4 3 2 1

EASY TO PUT ON 5 4 3 2 1

FITS OVER DIFFERENT CLOTHES 5 4 3 2 1

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Customer Satisfaction – existing products fulfilling specified requirements.

Improvement Ratio = Planned Performance / Existing Performance

Sales Point – weight for marketability

Overall Weighting = Importance Weighting x Improvement Ratio X Sales Point


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Comfortable

Easy to Put On

Fits over different clothes

Impo

rtan

ce W

eigh

ting

Cus

tom

er S

atis

fact

ion

Plan

ned

Satis

fact

ion

Impr

ovem

ent R

atio

Sale

s Po

int

Ove

rall

Wei

ghtin

g

Impo

rtan

ce W

eigh

ting

Cus

tom

er S

atis

fact

ion

Plan

ned

Satis

fact

ion

Impr

ovem

ent R

atio

Sale

s Po

int

Ove

rall

Wei

ghtin

g

5

1

2

2

1

3

5

2

4

2.5

2

1.3

1.4

1.0

1.1

17.5

2

2.9

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3(d) Technical Requirements

Engineering Characteristics, Voice of the Company.

Identify Measurable Characteristics related to Customer Requirements.

Direction of change included to lead to improvement of product performance.

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Critical Question:

How significant is technical requirement A in satisfying customer requirement B?

3(e) Interrelationships

Between customer requirements and technical requirements

Translation and correlation step Critical to generate consensus between

development team and customers.

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3(e) Interrelationships

6.0Safe

11.2

3.0

Technical Priority

Light weight

Does not restrict movement

6.0Safe

11.2

3.0

Technical Priority

Light weight


Har

ness

wei

ght

Web

bing

str

engt

h

# of

buc

kles

High -

Medium -

Low -

Ove

rall

Wei

ghti

ng

(9)

(3)

(1)

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3(f) “The Roof”

Considers impact of technical requirements on each other

Feature to feature comparison Augment or impede?

Critical Question: Does improving one requirement cause a

deterioration or improvement in another requirement?

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+ positive/supporting

Mee

ts s

tand

ards

Har

ness

wei

ght

Web

bing

str

engt

h

Pad

ding

thic

knes

s Legend

- negative/tradeoff

3(f) “The Roof”

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3(g) Targets

Summarize previous steps

Draw conclusions Consists of:

Technical Priorities Competitive

Benchmarks Final Product Targets

Results from previous steps: Customer requirements Prioritized customer

requirements Technical requirements Correlated requirements Feature

interdependencies

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3(h) Technical Priorities

6.0Safe

11.2

3.0

Technical Priority

Light weight


6.0Safe

11.2

3.0

Technical Priority

Light weight


Har

ness

wei

ght

Web

bing

str

engt

h

# of

buc

kles

High -

Medium -

Low -

Ove

rall

Wei

ghti

ng

(9)

(3)

(1)

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3(i) Competitive Benchmarks

Competitor #2

Existing System

Competitor #1

Competitor #2

Existing System

Competitor #1W

ebbi

ng s

tren

gth

Mee

ts s

tand

ards

Pad

ding

thic

knes

s

# of

buc

kles

Har

ness

wei

ght

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Target System

Web

bing

str

engt

h

Mee

ts s

tand

ards

Pad

ding

thic

k nes

s

# o f

bu c

kles

Har

ness

wei

ght

3(j) Final Product Targets

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3(k) House of Quality Summary

Inputs: Customer requirements Technical requirements Customer priorities Market reality / competitive analysis Organization’s strengths & weaknesses

Outputs Prioritized technical requirements Measurable, testable goals

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Exercise 2 – Build a House of Quality

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3(l) House of Quality Pros and Cons

Pros: Generates specific technical requirements Requirements are traceable Follows a repeatable, quantitative process Effectively translates Voice of the Customer Records rationale for each technical requirement

Cons: Time-consuming process for >10 requirements Data storage, manipulation and maintenance costs Very dependent on customer requirement gathering Inflexible to changing requirements; must recalculate

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4. QFD Life Cycle Comparisons

QFD?

CLEANROOM SASD

?

PD

RADJAD

RUP

XP

?? ?

?SSM

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4(a) QFD and Cleanroom

[SAIC, 2001]

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4(b) QFD and SASD

EnvironmentalModels

BehaviouralModels

ImplementationModels

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4(c) QFD vs. JAD

JAD is a communication-focused approachQFD is a Quality-focused approach

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4(d) QFD and PD

Workers and Designers work together

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4(e) QFD vs. RAD

QUALITY SPEED

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4(f) QFD vs. SSM

[Wilson, 2001]

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4(g) QFD and RUP

[Ronin, 2001]

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4(h) QFD and XP

[Wells, 2001]

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5. Conclusions


?

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5. Conclusions (Cont.)


?

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5. Conclusions (Cont.)


?

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QFD Designer

QFD Designer Business Improvement Software

Templates to define various aspects of QFD Icons, graphs, simplify add/delete

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References

qfd.ppt

Documents

Transcript of qfd.ppt